In geographic areas which are prone to having high wind events, such as hurricanes and the like, the need exists for the protection of openings, such as windows and doors, in buildings. Otherwise, if the high winds or wind-borne debris breaches the integrity of the structure by destroying a window or door, severe damage to the structure can be expected.
In its most simple form, one type of known protection device which can be utilized is a simple sheet of plywood which can be attached to the structure so as to cover the openings thereof. However, this “boarding up” procedure is not only time consuming, when time is usually of the essence, but also can disfigure the exterior of the structure upon frequent installation and removal. Moreover, storing and maintaining an inventory of plywood sheets can be problematic.
As a result, a number of temporarily installable or permanently installed devices have been developed to be used as alternatives to plywood. For example, metallic shutters consisting of a plurality of hinged slats can be provided adjacent to a window and can be rolled up by a hand crank or a motor when not in use. However, these devices are not only costly, but also they do not provide the necessary seal irrespective of whether they are mounted on the windward or leeward side of the building.
More recently, fabric-based systems have been developed which are much less costly than the metallic shutters or other devices, and which can provide a seal for the openings in the structure. In their simplest form, these systems include a sheet of fabric which is strong enough to withstand high winds and the forces of wind borne debris without rupturing. These fabric sheets may be sealed on all four edges, thus providing a seal for the structure even if the glass of a window, for example, has been broken.
In some such systems, the fabric can be rolled up and stored in a housing or header much like a conventional window shade. These devices usually are provided with a spring-based counterbalance and drive system. A problem associated with these devices is that when the fabric is impacted during a high wind event, the drive or counterbalance system can be damaged, or the fabric curtain can be payed out to an undesired extent, due to the impact of the forces being transferred to the drive or counterbalance components. The result of damage or failure of these components is that repair or replacement thereof must take place before the covering can be operated to open after the passage of the high wind event.